1. Field of the Invention
This invention relates to projected button display systems and more specifically to projected button display systems utilized with control/management systems.
2. Description of the Related Art
Within the aircraft cabin, the volume available for discrete switches, switch panels and small LCD displays has diminished to the point where airframers are restricting the depth of these, to the point where they are very difficult to place in the side ledge.
There are numerous patents that have issued that have involved advances in display systems for on-board entertainment systems. These include, for example, the following patents:
U.S. Pat. No. 7,148,935 entitled “On-Board Entertainment System Entertainment Display Retractor Position Sensor”, issued to C. Ho, et al., discloses a position sensor for determining the relative physical location of a movable item via a combination of a sensor and an indicator plate affixed to an actuator device.
U.S. Pat. No. 6,424,386 entitled “Liquid Crystal Display Device”, issued to T. Shimizu, discloses a liquid crystal display device comprising a housing mounted to a ceiling member of an airplane. An image control unit is fixed to the housing, and a liquid crystal display is fixed to a main shaft positioned at a center of rotation. In a retracting unit, a liquid crystal panel of the liquid crystal display is opposed to the image control unit, and stored inside a cover surrounding the housing. The whole height of the liquid crystal display device may be reduced, so as to secure the overhead clearance of the passengers.
In vehicles and particularly in aircraft minimizing size, weight, and power consumption of all systems on board is a significant discriminator when selecting equipment. Due to the limited space on vehicles, minimizing the equipment size allows for better utilization of passenger space in the cabin.
The technology of a Pico projector (also known as a handheld projector, pocket projector or mobile projector) is an emerging technology that applies the use of a handheld device. It is a response to the emergence of compact portable devices such as mobile phones, personal digital assistants, and digital cameras which have sufficient storage capacity to handle presentation materials but little space to accommodate an attached display screen. Handheld projectors involve miniaturized hardware and software that can project digital images onto any nearby viewing surface, such as a wall. The system comprises four main parts: the electronics, the light sources (e.g. LED or laser), the combiner optic, and the scanning mirrors. First, the electronics system turns the image into an electronic signal. Next the electronic signals drive light sources with different colors and intensities down different paths. In the combiner optic the different light paths are combined into one path demonstrating a palette of colors. Finally, the mirrors copy the image pixel by pixel and can then project the image. This entire system is compacted into one very tiny chip. An important design characteristic of a handheld projector is the ability to project a clear image, regardless of the physical characteristics of the viewing surface.
(http://en.wikipedia.org/wiki/Handheld_projector[5/17/2010])
In projector systems “keystoning” may be problematic. “Keystoning” occurs when a projector is aligned non-perpendicularly to a screen, or when the projection screen has an angled surface. The image that results from one of these misalignments will look trapezoidal rather than square. There are basically two methods of keystone correction, manual and digital. Manual keystone correction is essentially a physical adjustment to the lens of the projector so that it projects at an angle higher or lower than it would be if it were on a flat surface. Digital correction involves altering the image before it reaches the projection lens.
(http://www.projectorpeople.com/resources/keystone-correction.asp[6/6/2010])
Although pico projectors have been utilized in a variety of applications those applications have not included aircraft systems.
“Virtual” keyboards are becoming more and more commercialized. An optical virtual keyboard optically detects and analyses human hand and finger motions and interprets them as operations on a physically non-existent input device like a surface having painted keys. Celluon, Inc., Seoul, Korea, manufactures a virtual keyboard marketed under the trademark “Magic Cube.”